CN1544474A - Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent - Google Patents
Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent Download PDFInfo
- Publication number
- CN1544474A CN1544474A CNA2003101137889A CN200310113788A CN1544474A CN 1544474 A CN1544474 A CN 1544474A CN A2003101137889 A CNA2003101137889 A CN A2003101137889A CN 200310113788 A CN200310113788 A CN 200310113788A CN 1544474 A CN1544474 A CN 1544474A
- Authority
- CN
- China
- Prior art keywords
- quick
- fried
- cellulose
- described method
- steam
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229920002678 cellulose Polymers 0.000 title claims abstract description 46
- 239000001913 cellulose Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 32
- 239000002904 solvent Substances 0.000 title claims abstract description 14
- 230000004048 modification Effects 0.000 title claims abstract description 7
- 238000012986 modification Methods 0.000 title claims abstract description 7
- 239000002023 wood Substances 0.000 title claims abstract description 7
- 238000005516 engineering process Methods 0.000 title claims description 9
- 238000004880 explosion Methods 0.000 title description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 51
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000002253 acid Substances 0.000 claims abstract description 10
- 238000004090 dissolution Methods 0.000 claims abstract description 7
- 239000011121 hardwood Substances 0.000 claims abstract description 6
- 239000011122 softwood Substances 0.000 claims abstract description 6
- 239000005357 flat glass Substances 0.000 claims abstract description 4
- 239000002671 adjuvant Substances 0.000 claims abstract 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 20
- 239000000243 solution Substances 0.000 claims description 16
- 239000004202 carbamide Substances 0.000 claims description 12
- XSQUKJJJFZCRTK-UHFFFAOYSA-N urea group Chemical group NC(=O)N XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 12
- 210000003205 muscle Anatomy 0.000 claims description 11
- 238000001556 precipitation Methods 0.000 claims description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 8
- 239000004627 regenerated cellulose Substances 0.000 claims description 8
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- 238000006116 polymerization reaction Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- 238000009987 spinning Methods 0.000 claims description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 4
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 238000007766 curtain coating Methods 0.000 claims description 4
- 239000012528 membrane Substances 0.000 claims description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- 239000002994 raw material Substances 0.000 claims description 4
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 239000012752 auxiliary agent Substances 0.000 claims description 2
- 238000000280 densification Methods 0.000 claims description 2
- 230000007613 environmental effect Effects 0.000 claims description 2
- 238000011010 flushing procedure Methods 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 238000010298 pulverizing process Methods 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical group Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims 2
- 238000007605 air drying Methods 0.000 claims 2
- 230000005540 biological transmission Effects 0.000 claims 1
- 239000007799 cork Substances 0.000 claims 1
- 230000009189 diving Effects 0.000 claims 1
- 238000007654 immersion Methods 0.000 claims 1
- 238000002386 leaching Methods 0.000 claims 1
- 239000003446 ligand Substances 0.000 claims 1
- -1 salt compound Chemical class 0.000 claims 1
- 230000011218 segmentation Effects 0.000 claims 1
- 238000002791 soaking Methods 0.000 claims 1
- 239000007921 spray Substances 0.000 claims 1
- 230000008961 swelling Effects 0.000 claims 1
- 238000005406 washing Methods 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 13
- 230000000704 physical effect Effects 0.000 abstract 1
- 235000010980 cellulose Nutrition 0.000 description 33
- 239000000835 fiber Substances 0.000 description 16
- 238000012545 processing Methods 0.000 description 7
- 229920001131 Pulp (paper) Polymers 0.000 description 6
- 230000008014 freezing Effects 0.000 description 6
- 238000007710 freezing Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 229920000297 Rayon Polymers 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 229960005419 nitrogen Drugs 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- KFSLWBXXFJQRDL-UHFFFAOYSA-N Peracetic acid Chemical compound CC(=O)OO KFSLWBXXFJQRDL-UHFFFAOYSA-N 0.000 description 2
- 238000004061 bleaching Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 235000013311 vegetables Nutrition 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical compound NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 1
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- 241000282994 Cervidae Species 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- SJRXVLUZMMDCNG-UHFFFAOYSA-N Gossypin Natural products OC1C(O)C(O)C(CO)OC1OC1=C(O)C=C(O)C2=C1OC(C=1C=C(O)C(O)=CC=1)=C(O)C2=O SJRXVLUZMMDCNG-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 241001275902 Parabramis pekinensis Species 0.000 description 1
- 229920002522 Wood fibre Polymers 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- QKSIFUGZHOUETI-UHFFFAOYSA-N copper;azane Chemical compound N.N.N.N.[Cu+2] QKSIFUGZHOUETI-UHFFFAOYSA-N 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000007380 fibre production Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- SJRXVLUZMMDCNG-KKPQBLLMSA-N gossypin Chemical compound O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@H]1OC1=C(O)C=C(O)C2=C1OC(C=1C=C(O)C(O)=CC=1)=C(O)C2=O SJRXVLUZMMDCNG-KKPQBLLMSA-N 0.000 description 1
- 239000005457 ice water Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 230000009719 regenerative response Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000010257 thawing Methods 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 239000002025 wood fiber Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Images
Landscapes
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
The invention relates to the modified physical property of the supramolecular structure for pure natural wood cellulose and the dissolution process in the new solvent, wherein a high pressure vapor flash blast process is utilized to carry out structure modification to water or/and diluted acid immersed natural pure hardwood and soft wood cellulose at supermolecule level, and environmental-friendly, low-priced, low concentration NaOH / adjuvant new pattern dissolvent system is used to completely dissolve the modified cellulose, and a cellulose film with compact interior structure is obtained by further flowing the solution on the plate glass or film drawing, placing into diluted acid solution of a finite concentration for congelation and film forming, and purifying and airing.
Description
Technical field
This patent belongs to the structurally-modified and dissolving technology of natural wood cellulose.It belongs to technical field of polymer materials, and its country classification number is C08.
Background technology
The cellulosic fibre production technique has experienced very long evolutions such as cuprammonium process, viscose process and solvent method.The cuprammonium process produce cellulose fibers, the pollution of its production process and equipment corrosion are serious and technology is loaded down with trivial details, are eliminated substantially.Viscose fiber has good physical and mechanical properties and good water absorbability, ventilation property, dyeability, static resistance and is easy to graft modification; But the same with copper ammonia fibre, viscose fiber is also emitted CS in process of production
2And H
2Toxic gas and zinc-containing waters such as S pollute empty G﹠W, and ecotope is destroyed, and also have the solvent recuperation problem simultaneously, and this just makes further developing of viscose fiber be affected.
It is to be used for fodder production the earliest that steam dodges quick-fried (Steam Explosion) technology, and the high efficiency separation of vegetable fibre as conversion technology, is used for the gasification of organism etc.Nineteen twenty-seven, Mason at first put forward, and obtained patent.Researchists such as the U.S., Canada, New Zealand, France and China have carried out dodging the further research of quick-fried method slurrying.Except dodge with hot high pressure steam quick-fried, also useful peracetic acid, nitrogen etc. realize to dodge quick-fried process.Chen Yuru has introduced a kind of suitable vegetable fibre and has steamed quick-fried handler in its patent (CN2208589Y), but makes the not suitable pure wood pulps plate of alpha-cellulose content in 94%～98% scope carry out not report of modification on the supramolecule level.
People (Journal of Applied Polymer science such as early 1990s Laszkiewicz B., Vol.50,1993:27-34) studied the solubility property of cellulose III in NaOH solution, thought that adding thiocarbamide, acrylamide etc. can promote cellulose dissolution.People (British Polymer Journal such as Japanese soon scholar Kamide, Vol.22,1990:73-83) under certain condition, pulp is carried out steam dodge quick-fried processing, obtain alkali soluble fiber element, in 4 ℃ of NaOH aqueous solution that can be dissolved in finite concentration (8.4%) fully, (regenerated fibers such as Shao Ziqiang and deer red rock, Vol.1,2001:1-3) also once with regard to the sudden strain of a muscle of pure water steam is quick-fried cellulose modified result of study being reported, is to form gel easily at the dissolution process solution system but utilize the deficiency of this method, causes film forming to become silk, pure in addition steam treatment its to dodge the quick-fried process dwell time long partially, the pressure maintaining performance of equipment is proposed higher requirement.Zhang Lina teaches (PolymerJournal PY, Vol.32,2000:866-870) adopt the acid solution degraded, the polymerization degree of wood pulp and gossypin is dropped to below 400, again it is dissolved in certain density NaOH buck/urea system, think concentration that Mierocrystalline cellulose after the acidolysis is dispersed in the 6wt%NaOH/4wt% aqueous solution of urea below 5wt%, through low temperature (15～-5 ℃) down behind freezing 12～24h, through thawing and violent stirring can reach dissolving fully.
The present invention dodges quick-fried physically modified and two approach of mixed solvent dissolving by steam, Mierocrystalline cellulose is dissolved with diluted acid solidify.Dodge quick-fried at pure wood cellulose, after water logging (or/and acidleach), again with its moisture control to certain limit.Steam through certain pressure and temperature dodges quick-fried then, obtain+below 6 ℃ in the 9wt%NaOH/1wt% aqueous solution of urea consoluet innovation wood fiber, dissolving forms the solution of certain viscosity, and film forming and reel off raw silk from cocoons and solidify in diluted acid obtains having certain intensity and flexible film and silk again.
Summary of the invention
The invention belongs to the physically modified of pure natural wood cellulose supramolecular structure and dissolving method in novel solvent.This patent adopts that a kind of physically modified technology--high pressure steam is dodged quick-fried technology, to through water (or/and) the natural pure hardwood of diluted acid preimpregnation, softwood cellulose carries out structurally-modified in the supramolecule level, adopt environmental protection simultaneously, cheap, the NaOH/ auxiliary agent novel dissolvent system of lower concentration, Mierocrystalline cellulose after the modification is dissolved fully, further with this solution curtain coating or membrane on sheet glass, put into certain density dilute acid soln freezing film then, dry the plain film of the internal structure feltwork that obtains tensile strength 88.7MPa and elongation at break 4.2% after the cleaning, the silk of extruding by exerting pressure is handled through same solidifying and is obtained doing the strong 285.52.12cN/dtex that is, wet is the strand of 142.31.06cN/dtex by force.
High pressure steam of the present invention is dodged quick-fried system, mainly be to realize high temperature, high pressure and moments three big characteristics, satisfy safety and handled easily simultaneously.When quick-fried, realize quickly discharging material in order to dodge in moment, the interior finish 1.6～0.8 (6～7 grades) of dodging quick-fried device is dodged angle Selection 2 θ of quick-fried device discharge port=50～60 °, and Fig. 1 is the longitudinal section structural map that dodges quick-fried device embodiment, and among the figure, 1-dodges quick-fried valve; 2-brasses joint; The 3-brasses; The 4-thermal insulation layer; The 5-inner core; The 6-fastening cover; The 7-charging opening; 8-pneumatic tube and valve; 9-thermometric electricity coupling sleeve pipe.
Dodge quick-fried system limits condition: pressure high limit 5.0,300 ℃ of upper temperature limits (safety coefficient of pressure and temperature is 1.5), 0.2s moment dodges quick-fried, 10 ℃/min of intensification degree speed; Overlap even heating system with brasses; The high-duty boiler vapour generator can provide and dodge the quantity of steam of quick-fried usefulness three times, adopts the electric stove wire heating system, and is furnished with water filling and cleans water drain valve; Dodge quick-fried device and vapor generation actuator temperature and pressure by the thermocouple assay automatic control and adjustment, and be furnished with security system.
The present invention pulls the quick-fried treatment system equipment of sudden strain of a muscle synoptic diagram to pure wood pulp and sees Fig. 2.Among the figure, the 1-water drain valve; The 2-nitrogengas cylinder; The 3-high pressure steam generator; 4-thermometric electricity coupling; 5, the 7-valve; 6, the 8-tensimeter; 9-transfer port and valve; The 10-gas pipe line; The 11-water inlet pipe; 12-pneumatic tube and valve; The 13-threeway; 14-inlet pipe and valve; The 15-tensimeter; The 16-valve; 17-thermometric electricity coupling; 18-dodges quick-fried device; 19-support and stationary installation; Control of 20-temperature and regulation system; The universal rotary valve of 21-; 22-receives top cover; 23-material receptor.
Hardwood and soft wood pulp raw material are provided by Baoding Swan Co., Ltd., and alpha-cellulose content is in 94%～98% scope; Also comprise " leaflet " board bleaching broad-leaved and " sun " board bleaching needle that Beijing papermaking institute provides in addition; NaOH, ethanol, urea, acetone and required other medicine etc. are analytical pure.
Dodge the processing of quick-fried preceding raw material: wood-pulp board will pass through pulverization process before sudden strain of a muscle is quick-fried, utilize mechanical shearing, with its particle that is ground into 3 * 3～10 * 10mm size range, is preferably about 5 * 5～7 * 7mm.Steam dodge quick-fried before, usually 1 part of butt Mierocrystalline cellulose is immersed in 20 parts of distilled water, under 25 ℃ or room temperature, wood-pulp board soaks 12～15h, unnecessary water is removed (2000rpm) with ultracentrifuge and is carried out 5min, is adjusted to Mierocrystalline cellulose: water=1: 1, i.e. water content 100wt%.
Processing is all even carries out water logging 3～9h earlier to dodging quick-fried sample rapidly in order to make, and carries out diluted acid again and soaks 1～3h, and vacuum filtration is then put into the quick-fried device of sudden strain of a muscle and dodged quick-fried.
Dodge quick-fried treating processes: the present invention is adjusted to 80wt%～150wt% with cellulosic water content before sudden strain of a muscle is quick-fried, put it into then in the quick-fried device 18 of the sudden strain of a muscle that is heated to preset temperature, closes and dodges quick-fried device.System begins to heat up, (temperature is that the saturation pressure of 456K～525K hot steam correspondence is that 1.0MPa～4.9MPa) leading to people from vapour generator 3 dodges the quick-fried device 18 to instant hot steam with preset temperature and pressure, wait to dodge quick-fried device constant pressure behind desirable value, isolate and dodge quick-fried device, and pressurize 10s is to 30s, then suddenly open the spherical valve (parts 1 among Fig. 1) that links to each other with vapor pipe by pneumavalve, the Mierocrystalline cellulose that sudden strain of a muscle is produced is by pressure reduction, enter rotoclone collector 22, Mierocrystalline cellulose after the processing is collected in the 80 purpose copper mesh, after the discharging after filtration, clear water, acetone repeatedly cleans, and dries processing then.
The configuration of solvent system: take by weighing a certain amount of solid NaOH and urea, add deionized water to required concentration of ordinary dissolution, the amount of NaOH is at 8.00wt%～10.00wt%, and the amount of urea is at 0.50wt%～3.00wt%.
Cellulosic dissolving: take by weighing 95 parts of above-mentioned preceding two kinds of solution and place there-necked flask, ice-water bath is cooled to below 6 ℃, adds 5 parts of Mierocrystalline celluloses after dodging quick-fried processing, intermittently stirs 6～8h fast with the reinforcement electric mixer.Whole dissolution process temperature remains on 3～6 ℃.
The preparation of peptizer: adopt H
2SO
4/ silicate system is as precipitation bath.
Film process: with the quick-fried cellulose solution of sudden strain of a muscle consoluet, that have certain viscosity, drop on the sheet glass and carry out, carry out curtain coating or membrane, it is immersed in the corresponding precipitation bath rapidly then, with 60 ℃, 25 ℃ flushing with clean water, on the screen cloth of certain pore size, dry naturally then behind 20～30min.
The polymerization degree of resulting regenerated cellulose film, degree of crystallinity and surface crystallization size see Table 1 with the quick-fried cellulosic material contrast of sudden strain of a muscle according to the present invention.As seen, cellulosic degree of polymerization also slightly reduces after the film forming, and this shows that Mierocrystalline cellulose in dissolving and regenerative process, degraded has in various degree taken place equally, and precipitation bath concentration increases can the aggravation degraded.
Table 1 dodges the polymerization degree, degree of crystallinity and the surface crystallization size of quick-fried Mierocrystalline cellulose and regenerated cellulose film
Degree of crystallinity surface crystallization size
The sample polymerization degree
(％) 101 101 002
Dodge quick-fried Mierocrystalline cellulose 358 78.14 41.14 59.63 38.62
Film-2 336 65.54 38.07 60.38 89.25
Film-3 330 64.82 37.85 64.32 80.23
Film-5 320 65.14 38.29 77.64 60.34
By Fig. 3 is the surface (a) and cross section (b) SEM photo of film, and as seen, the surface of film has vesicular structure.Along with sulfuric acid concentration is increased to 20wt% from 5wt%, surface apertures is increased to 230nm from 50nm.And there is a great difference in the internal structure of film, the internal structure of the film that 5wt% sulfuric acid solidifies is very fine and close, amplify 30000 times and also do not observe clearly hole, but increase along with sulfuric acid concentration, especially when sulfuric acid concentration greater than 15% the time, film presents tangible pore space structure, and the aperture is between 80～130nm.This shows that regenerated cellulose film can be used for filtering, and can change the aperture of film by the concentration of adjusting precipitation bath.In addition, the aperture, inside of regenerated cellulose film is less than surface apertures.When Mierocrystalline cellulose liquid film contact precipitation bath, the surface at first is neutralized, and forms the thin gel coat of one deck.Along with the prolongation of time, the low-molecular-weight component (Na in the Mierocrystalline cellulose liquid film
+, OH
-Deng) and precipitation bath between carry out the phase mutual diffusion owing to neutralize, saltout, solidify and Decomposition, make Mierocrystalline cellulose obtain separation, gel coat is more and more thicker.Gel phase is mainly by Mierocrystalline cellulose and low molecular weight substance (H
2O, H
+Deng) form.5wt% sulfuric acid is as precipitation bath, be to avoid solidifying of top layer too fierce, otherwise forming one deck lacks flexibility and crisp hard cortex, low-molecular-weight component in the Mierocrystalline cellulose liquid film and the phase mutual diffusion between the precipitation bath have been limited, delayed solidifying of liquid film inside, increased the textural difference of gel phase, so that regenerated cellulose film produces porous, loose structure.
Adopt the present invention obtain the tensile strength (σ of film
t) and elongation at break (ε
t) concern by shown in Figure 4.As seen, when sulfuric acid concentration was 2wt%, because setting rate is very slow, film forming mechanical property was not fine.And when sulfuric acid concentration reaches 5wt%, suitable with the liquid film effect, and the densification of film internal structure, it is maximum that tensile strength and elongation at break all reach, and is respectively 88.7MPa and 4.2wt%.When continuing to increase sulfuric acid concentration,, also make inner aperture increase, the tensile strength of regenerated cellulose film and elongation at break are reduced except increasing to cellulosic Degradation.
Cellulose solution becomes silk: the rare NaOH/ urea solvent system cellulose solution that will be dissolved into transparence is put into spinning pot, inflated with nitrogen after the vacuum defoamation (or pressurized air), make spinning pot arrive certain pressure, open spinning nozzle inlet pipe valve, solution is by behind the spinning nozzle, and the solution thread enters precipitation bath with certain speed, carries out regenerative response, generate nascent strand, obtain the Mierocrystalline cellulose strand through certain tensile drawing-off effect again.Processing conditions:
Strand is at 80 ℃ of temperature, drying time 4h; Precharge pressure 100g/20 root bar; Test: fiber number testing tool: gauging machine, the powerful machine of day gentle isodromicing elongation's type.
Scanning electron microscope: adopt the cryogenic freezing evaporation to prepare the scanning electron microscopic observation sample.Distillation obtained the exsiccant fiber after fiber yarn fractureed behind liquid nitrogen freezing, used the surface and the end face pattern of JEOLJSM-6700F type field-emission scanning electron microscopic observation fiber behind cross section and the surperficial metal spraying.
Testing method: carry out with reference to GB/T13758-92 viscose rayon filament yarn testing method.
Fig. 5 be rare NaOH/ urea solvent system cellulose solution taken out the silk stereoscan photograph.(a) chilled surfaces; (b) end face, normal temperature cuts off; (c) normal temperature surface and (d) freezing, figure fractures.The fiber strand silk pattern of handling from freezing and normal temperature as seen, desolventizing turns into causing the internal stress inequality, thereby causes and inside and outsidely shrink inconsistently, makes fibrous inside generation hole, texture ratio is more loose.But along with the increase of silk in the drafted degree of moulding process, filametntary structure is tending towards evenly, and hole almost disappears, and pulling speed difference and moulding temperature of solidification change the proper cellulosic fibre that will obtain high comprehensive performance of control.
It in the table 2 test result of single strand.Mierocrystalline cellulose is after SE handles, molecular structure own and crystalline state change, be dissolved in rare NaOH/ urea solvent system, after the regeneration moulding, strand degree of crystallinity reduces (Mierocrystalline cellulose crystal I is converted into Mierocrystalline cellulose crystal II), and cellulose regenerated structure is tight, the strand rigidity is outstanding, the inside and outside uniformity in strand cross section, no skin-core structure, the strand transparency is higher.
The rare NaOH/ urea of table 2 solvent system regenerated cellulose strand fiber number, strength and elongation
The parameter fiber number, dtex does strong, and cN is wet strong, and cN is dried to be stretched, and % is wet to stretch %
133.0 243 136 6.5 10.4
137.2 301 128 9.3 11.4
130.6 298 168 6.2 15.4
138.7 313 142 7.8 13.0
135.5 289 142 6.5 10.6
131.2 289 138 7.1 11.4
Mean value 134.4 285.5 142.3 7.2 12.0
2.12cN/dtex 1.06cN/dtex
Claims (11)
1. natural hard, physically modified of softwood cellulose supramolecular structure and the dissolving method in novel solvent.Present method adopts steam to dodge quick-fried physically modified technology, natural hardwood, softwood cellulose are carried out physics time modification in the supramolecule level, adopt environmental protection, NaOH/ adjuvant system cheap, lower concentration simultaneously, it is dissolved fully, and make its curtain coating or membrane, exert pressure and reel off raw silk from cocoons, obtain having the regenerated cellulose film and the silk of certain toughness and intensity again through supersolidification.
2. according to right 1 described method, it is characterized in that adopting natural hardwood, the softwood cellulose of various materials, the polymerization degree is 800～1500, and alpha-cellulose content is a raw material at 94%～98% scope pure cellulose.
3. according to right 1 described method, raw material pulverizing to be grown up before it is characterized in that handling * particle of wide 3 * 3～10 * 10mm size range, be preferably about 5 * 5～7 * 7mm, soak through clear water, time is 3～9h, dilute acid soln through 0.5wt%～3wt% soaks again, and the time is 1～3h, and soaking temperature all is 20～30 ℃.Wanting centrifugal after the immersion or negative pressure leaching anhydrates, is 80wt%～150wt% scope through the negative pressure Air drying until its water content again.
4. according to right 1 described method, it is characterized in that the quick-fried system of the sudden strain of a muscle of adopting has steam generating system, steam transmission system, sudden strain of a muscle quick-fried device system and conditional parameter Controlling System.Pure wood cellulose dodges quick-fried treatment system, ultimate pressure 5.0MPa, and 300 ℃ of temperature, safety coefficient 1.5,0.2s moment dodges quick-fried, and the steam of 10 ℃/min of intensification degree speed dodges quick-fried system.The interior finish of dodging quick-fried device is 1.6～0.8, dodges angle Selection 2 θ of quick-fried device discharge port=50～60 °.
5. according to right 1 described method, it is characterized in that this system can be seeped into the elevated temperature heat steam moment emptying of cellulose materials inside with diving, realize that cellulosic supramolecular structure changes: it is 1.5MPa that hardwood is dodged quick-fried condition, 20s; Cork is 1.0MPa, 12s.
6. according to right 1 described method, the pulpous state sample that it is characterized in that dodging after quick-fried will filter or centrifugal anhydrating immediately, handles through carrying out the negative pressure Air drying behind ethanol, the washing with acetone again.
7. according to right 1 described method, the sample dissolution solvent for use that it is characterized in that dodging after quick-fried is a NaOH/ adjuvant water solution system, and the two content in the aqueous solution of NaOH and auxiliary agent is respectively 9wt% ± 0.4wt%, 1wt% ± 0.2wt%.Solubility promoter is a urea, and its feature is that also the thiocarbamide that urea can be measured equally substitutes.
8. according to right 1 described method, it is characterized in that and will dodge sample dissolution after quick-fried at right 5 described solvent systems, temperature will control and be no more than+and 6 ℃, dissolving wants segmentation, intermittent type to stir, and all dissolves until the swelling clout.
9. according to right 1 described method, it is characterized in that dissolving the back cellulose solution, curtain coating or membrane on sheet glass, putting into precipitation bath then solidifies, peptizer can be hydrochloric acid, sulfuric acid and salt compound ligand thereof, acid concentration is 4wt%～10wt%, with 60 ℃, 25 ℃ flushing with clean water, dries behind 20～30min again.
10. according to right 1 described method, it is characterized in that when sulfuric acid concentration reaches 5wt%, the densification of resulting film internal structure, it is maximum that tensile strength and elongation at break all reach, and is respectively 88.7MPa and 4.2wt%.
11. according to right 1 described method, it is characterized in that solution is put into spinning pot, inflated with nitrogen after vacuum defoamation waits to reach spray silk behind the certain pressure, the solution thread enters precipitation bath with certain speed, obtains the Mierocrystalline cellulose strand through certain tensile drawing-off effect again.The dried strong 285.52.12cN/dtex of strand, wet strong 142.31.06cN/dtex.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2003101137889A CN100354309C (en) | 2003-11-25 | 2003-11-25 | Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2003101137889A CN100354309C (en) | 2003-11-25 | 2003-11-25 | Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1544474A true CN1544474A (en) | 2004-11-10 |
| CN100354309C CN100354309C (en) | 2007-12-12 |
Family
ID=34336972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2003101137889A Expired - Fee Related CN100354309C (en) | 2003-11-25 | 2003-11-25 | Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100354309C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009018709A1 (en) * | 2007-08-03 | 2009-02-12 | Zhen Fang | A method and an equipment of dissolving ligneous cellulosic biologic materials completely |
| CN101381970B (en) * | 2007-09-05 | 2011-06-15 | 中国科学院过程工程研究所 | Method for co-producing paper pulp and fuel ethanol by wild grass on forest land |
| CN102504559A (en) * | 2011-11-04 | 2012-06-20 | 山东省塑料研究开发中心 | Method for processing full-degradable and recyclable plastic by using natural straw |
| CN105801883A (en) * | 2016-03-25 | 2016-07-27 | 西南交通大学 | Method for preparing cellulose solution |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2208589Y (en) * | 1994-09-13 | 1995-09-27 | 南京化工学院 | Digester for vegetable cellulose |
| CN1105310A (en) * | 1994-10-13 | 1995-07-19 | 南京化工学院 | Method for manufacturing natural composite-fibrous board using plant cellulose material |
| JP3841179B2 (en) * | 1996-04-16 | 2006-11-01 | 旭化成ケミカルズ株式会社 | Fine cellulose suspension |
-
2003
- 2003-11-25 CN CNB2003101137889A patent/CN100354309C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009018709A1 (en) * | 2007-08-03 | 2009-02-12 | Zhen Fang | A method and an equipment of dissolving ligneous cellulosic biologic materials completely |
| CN101381970B (en) * | 2007-09-05 | 2011-06-15 | 中国科学院过程工程研究所 | Method for co-producing paper pulp and fuel ethanol by wild grass on forest land |
| CN102504559A (en) * | 2011-11-04 | 2012-06-20 | 山东省塑料研究开发中心 | Method for processing full-degradable and recyclable plastic by using natural straw |
| CN105801883A (en) * | 2016-03-25 | 2016-07-27 | 西南交通大学 | Method for preparing cellulose solution |
| CN105801883B (en) * | 2016-03-25 | 2018-05-01 | 西南交通大学 | A kind of method for preparing cellulose solution |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100354309C (en) | 2007-12-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Yang et al. | Effects of preparation methods on the morphology and properties of nanocellulose (NC) extracted from corn husk | |
| RU2735138C1 (en) | Cellulose nanofibers modified with sulfuric acid esterification method and cellulose nanofibres production method | |
| US9103069B2 (en) | Method for dry spinning neutral and anionically modified cellulose and fibres made using the method | |
| WO2007121609A1 (en) | The use of aqueous solution of sodium-hydroxide and sulfourea in producing cellulose products in pilot-scale | |
| JP7129710B2 (en) | CELLULOSE NANOFIBER AND SHEET-LIKE MATERIAL COMPOSITION THEREOF, AND METHOD FOR MANUFACTURING THEM | |
| Yamashiki et al. | Characterisation of cellulose treated by the steam explosion method. Part 3: Effect of crystal forms (cellulose I, II and III) of original cellulose on changes in morphology, degree of polymerisaion, solubility and supermolecular structure by steam explosion | |
| Lazić et al. | Effect of chemical treatments on the chemical composition and properties of flax fibers | |
| US20140053995A1 (en) | Method for spinning anionically modified cellulose and fibres made using the method | |
| EP4021946B1 (en) | Cellulose pretreatment | |
| WO2001073172A1 (en) | Cellulosic materials having composite crystalline structure | |
| Campos et al. | Production of cellulose nanowhiskers from oil palm mesocarp fibers by acid hydrolysis and microfluidization | |
| CN108824067A (en) | A kind of p-aramid paper and preparation method thereof | |
| CN100354309C (en) | Steam flash explosion method modification of wood cellulose and its dissolving technology in novel solvent | |
| Saputro et al. | Preparation of micro-fibrillated cellulose based on sugar palm ijuk (Arenga pinnata) fibres through partial acid hydrolysis | |
| CN109576803A (en) | A kind of production method of chitin fiber | |
| CN108624972B (en) | Graphene/silicon compound, graphene/silicon compound/polyacrylonitrile composite fiber and preparation method thereof | |
| CN101046003A (en) | Process of producing viscose fiber with bamboo material | |
| SaifulAzry et al. | Effects of Polymorph Transformation via Mercerisation on Microcrystalline Cellulose Fibres and Isolation of Nanocrystalline Cellulose Fibres. | |
| Li et al. | Study on the structure and properties of viscose/wool powder blended fibre | |
| JP6847102B2 (en) | Manufacturing method of molded product | |
| KR20000067612A (en) | The chitosan fiber having high degree of strength and elasticity | |
| Jiang et al. | Investigation of a widely applicable process for extracting carboxyl-rich cellulose nanocrystal (CNC) | |
| Thang et al. | Eco-friendly Materials of Polymer Composites Based on Water Hyacinth Fibers/Roving | |
| Fan et al. | Degumming and characterization of palm fibers | |
| WO2002075029A1 (en) | Method for producing cellulose/cellulose triacetate fabrics |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20071212 Termination date: 20111125 |